The cargo material is guided wholly or partly by the stand pipe, the jib pipes, and where appropriate the link and the beam. Hydraulic cylinders are provided for adjusting the system, these effecting independently of one another the pivoting of the inner jib pipe relatively to the stand pipe and pivoting the outer jib pipe relatively to the inner jib pipe.
Apparatus of this kind is required, for example, for the onloading and offloading of tankers when the size of the tanker prevents offloading by means of flexible tubes. The pivoting system of the apparatus makes is possible to adjust the pipe line coupling of the outer jib pipe to the position of the coupling device provided on the ship, which position varies from ship to ship and also varies during transfer of cargo, and to remove the coupling away from the ship into a basic rest position.
An apparatus is known whose outer jib pipe in fact can also be withdrawn completely behind the vertical line of the dock edge. But this is achieved by pivoting the inner jib pipe beyond the vertical line behind the stand pipe. Now this proposal involves a number of disadvantages. Increasing the pivoting range of the inner jib pipe requires a special bell crank lever on the pivot bearing of the stand pipe, this lever being connected securely to the inner jib pipe. Also, disadvantageous angles result between this bell crank lever and the cylinder axis in the end positions of the apparatus, so that considerable forces have to be applied. The at least partial weight compensation of the pivotable part of the apparatus is also less precise, so that the forces which have to be applied are also increased as a result of this factor. To obviate a considerable tilting moment at right angles to the pivoting axis on the stand pipe, in addition, the inner jib pipe and the beam must be given a fork type of construction and the compensating or balance weight with the adjusting device must be made in two parts, therefore involving more outlay.